kex.h revision 224638 
1/* $OpenBSD: kex.h,v 1.52 2010/09/22 05:01:29 djm Exp $ */
2/* $FreeBSD$ */
3
4/*
5 * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27#ifndef KEX_H
28#define KEX_H
29
30#include <signal.h>
31#include <openssl/evp.h>
32#include <openssl/hmac.h>
33#ifdef OPENSSL_HAS_ECC
34#include <openssl/ec.h>
35#endif
36
37#define KEX_COOKIE_LEN	16
38
39#define	KEX_DH1			"diffie-hellman-group1-sha1"
40#define	KEX_DH14		"diffie-hellman-group14-sha1"
41#define	KEX_DHGEX_SHA1		"diffie-hellman-group-exchange-sha1"
42#define	KEX_DHGEX_SHA256	"diffie-hellman-group-exchange-sha256"
43#define	KEX_RESUME		"resume@appgate.com"
44/* The following represents the family of ECDH methods */
45#define	KEX_ECDH_SHA2_STEM	"ecdh-sha2-"
46
47#define COMP_NONE	0
48#define COMP_ZLIB	1
49#define COMP_DELAYED	2
50
51enum kex_init_proposals {
52	PROPOSAL_KEX_ALGS,
53	PROPOSAL_SERVER_HOST_KEY_ALGS,
54	PROPOSAL_ENC_ALGS_CTOS,
55	PROPOSAL_ENC_ALGS_STOC,
56	PROPOSAL_MAC_ALGS_CTOS,
57	PROPOSAL_MAC_ALGS_STOC,
58	PROPOSAL_COMP_ALGS_CTOS,
59	PROPOSAL_COMP_ALGS_STOC,
60	PROPOSAL_LANG_CTOS,
61	PROPOSAL_LANG_STOC,
62	PROPOSAL_MAX
63};
64
65enum kex_modes {
66	MODE_IN,
67	MODE_OUT,
68	MODE_MAX
69};
70
71enum kex_exchange {
72	KEX_DH_GRP1_SHA1,
73	KEX_DH_GRP14_SHA1,
74	KEX_DH_GEX_SHA1,
75	KEX_DH_GEX_SHA256,
76	KEX_ECDH_SHA2,
77	KEX_MAX
78};
79
80#define KEX_INIT_SENT	0x0001
81
82typedef struct Kex Kex;
83typedef struct Mac Mac;
84typedef struct Comp Comp;
85typedef struct Enc Enc;
86typedef struct Newkeys Newkeys;
87
88struct Enc {
89	char	*name;
90	Cipher	*cipher;
91	int	enabled;
92	u_int	key_len;
93	u_int	block_size;
94	u_char	*key;
95	u_char	*iv;
96};
97struct Mac {
98	char	*name;
99	int	enabled;
100	u_int	mac_len;
101	u_char	*key;
102	u_int	key_len;
103	int	type;
104	const EVP_MD	*evp_md;
105	HMAC_CTX	evp_ctx;
106	struct umac_ctx *umac_ctx;
107};
108struct Comp {
109	int	type;
110	int	enabled;
111	char	*name;
112};
113struct Newkeys {
114	Enc	enc;
115	Mac	mac;
116	Comp	comp;
117};
118struct Kex {
119	u_char	*session_id;
120	u_int	session_id_len;
121	Newkeys	*newkeys[MODE_MAX];
122	u_int	we_need;
123	int	server;
124	char	*name;
125	int	hostkey_type;
126	int	kex_type;
127	int	roaming;
128	Buffer	my;
129	Buffer	peer;
130	sig_atomic_t done;
131	int	flags;
132	const EVP_MD *evp_md;
133	char	*client_version_string;
134	char	*server_version_string;
135	int	(*verify_host_key)(Key *);
136	Key	*(*load_host_public_key)(int);
137	Key	*(*load_host_private_key)(int);
138	int	(*host_key_index)(Key *);
139	void	(*kex[KEX_MAX])(Kex *);
140};
141
142int	 kex_names_valid(const char *);
143
144#ifdef	NONE_CIPHER_ENABLED
145void	 kex_prop2buf(Buffer *, char *[PROPOSAL_MAX]);
146#endif
147
148Kex	*kex_setup(char *[PROPOSAL_MAX]);
149void	 kex_finish(Kex *);
150
151void	 kex_send_kexinit(Kex *);
152void	 kex_input_kexinit(int, u_int32_t, void *);
153void	 kex_derive_keys(Kex *, u_char *, u_int, BIGNUM *);
154
155Newkeys *kex_get_newkeys(int);
156
157void	 kexdh_client(Kex *);
158void	 kexdh_server(Kex *);
159void	 kexgex_client(Kex *);
160void	 kexgex_server(Kex *);
161void	 kexecdh_client(Kex *);
162void	 kexecdh_server(Kex *);
163
164void
165kex_dh_hash(char *, char *, char *, int, char *, int, u_char *, int,
166    BIGNUM *, BIGNUM *, BIGNUM *, u_char **, u_int *);
167void
168kexgex_hash(const EVP_MD *, char *, char *, char *, int, char *,
169    int, u_char *, int, int, int, int, BIGNUM *, BIGNUM *, BIGNUM *,
170    BIGNUM *, BIGNUM *, u_char **, u_int *);
171#ifdef OPENSSL_HAS_ECC
172void
173kex_ecdh_hash(const EVP_MD *, const EC_GROUP *, char *, char *, char *, int,
174    char *, int, u_char *, int, const EC_POINT *, const EC_POINT *,
175    const BIGNUM *, u_char **, u_int *);
176int	kex_ecdh_name_to_nid(const char *);
177const EVP_MD *kex_ecdh_name_to_evpmd(const char *);
178#else
179# define kex_ecdh_name_to_nid(x) (-1)
180# define kex_ecdh_name_to_evpmd(x) (NULL)
181#endif
182
183void
184derive_ssh1_session_id(BIGNUM *, BIGNUM *, u_int8_t[8], u_int8_t[16]);
185
186#if defined(DEBUG_KEX) || defined(DEBUG_KEXDH) || defined(DEBUG_KEXECDH)
187void	dump_digest(char *, u_char *, int);
188#endif
189
190#endif
191